1 /* $Id: plip.c,v 1.3.6.2 1997/04/16 15:07:56 phil Exp $ */
2 /* PLIP: A parallel port "network" driver for Linux. */
3 /* This driver is for parallel port with 5-bit cable (LapLink (R) cable). */
5 * Authors: Donald Becker <becker@scyld.com>
6 * Tommy Thorn <thorn@daimi.aau.dk>
7 * Tanabe Hiroyasu <hiro@sanpo.t.u-tokyo.ac.jp>
8 * Alan Cox <gw4pts@gw4pts.ampr.org>
9 * Peter Bauer <100136.3530@compuserve.com>
10 * Niibe Yutaka <gniibe@mri.co.jp>
11 * Nimrod Zimerman <zimerman@mailandnews.com>
14 * Modularization and ifreq/ifmap support by Alan Cox.
15 * Rewritten by Niibe Yutaka.
16 * parport-sharing awareness code by Philip Blundell.
17 * SMP locking by Niibe Yutaka.
18 * Support for parallel ports with no IRQ (poll mode),
19 * Modifications to use the parallel port API
24 * - Module initialization.
26 * - Make sure other end is OK, before sending a packet.
27 * - Fix immediate timer problem.
30 * - Changed {enable,disable}_irq handling to make it work
31 * with new ("stack") semantics.
33 * This program is free software; you can redistribute it and/or
34 * modify it under the terms of the GNU General Public License
35 * as published by the Free Software Foundation; either version
36 * 2 of the License, or (at your option) any later version.
40 * Original version and the name 'PLIP' from Donald Becker <becker@scyld.com>
41 * inspired by Russ Nelson's parallel port packet driver.
44 * Tanabe Hiroyasu had changed the protocol, and it was in Linux v1.0.
45 * Because of the necessity to communicate to DOS machines with the
46 * Crynwr packet driver, Peter Bauer changed the protocol again
47 * back to original protocol.
49 * This version follows original PLIP protocol.
50 * So, this PLIP can't communicate the PLIP of Linux v1.0.
54 * To use with DOS box, please do (Turn on ARP switch):
55 * # ifconfig plip[0-2] arp
57 static const char version[] = "NET3 PLIP version 2.4-parport gniibe@mri.co.jp\n";
61 Ideas and protocols came from Russ Nelson's <nelson@crynwr.com>
62 "parallel.asm" parallel port packet driver.
64 The "Crynwr" parallel port standard specifies the following protocol:
65 Trigger by sending nibble '0x8' (this causes interrupt on other end)
70 Each octet is sent as <wait for rx. '0x1?'> <send 0x10+(octet&0x0F)>
71 <wait for rx. '0x0?'> <send 0x00+((octet>>4)&0x0F)>
73 The packet is encapsulated as if it were ethernet.
75 The cable used is a de facto standard parallel null cable -- sold as
76 a "LapLink" cable by various places. You'll need a 12-conductor cable to
77 make one yourself. The wiring is:
80 D0->ERROR 2 - 15 15 - 2
81 D1->SLCT 3 - 13 13 - 3
82 D2->PAPOUT 4 - 12 12 - 4
84 D4->BUSY 6 - 11 11 - 6
85 Do not connect the other pins. They are
87 STROBE is 1, FEED is 14, INIT is 16
88 extra grounds are 18,19,20,21,22,23,24
91 #include <linux/module.h>
92 #include <linux/kernel.h>
93 #include <linux/types.h>
94 #include <linux/fcntl.h>
95 #include <linux/interrupt.h>
96 #include <linux/string.h>
97 #include <linux/if_ether.h>
99 #include <linux/errno.h>
100 #include <linux/delay.h>
101 #include <linux/init.h>
102 #include <linux/netdevice.h>
103 #include <linux/etherdevice.h>
104 #include <linux/inetdevice.h>
105 #include <linux/skbuff.h>
106 #include <linux/if_plip.h>
107 #include <linux/workqueue.h>
108 #include <linux/spinlock.h>
109 #include <linux/completion.h>
110 #include <linux/parport.h>
111 #include <linux/bitops.h>
113 #include <net/neighbour.h>
115 #include <asm/system.h>
117 #include <asm/byteorder.h>
119 /* Maximum number of devices to support. */
122 /* Use 0 for production, 1 for verification, >2 for debug */
126 static const unsigned int net_debug = NET_DEBUG;
128 #define ENABLE(irq) if (irq != -1) enable_irq(irq)
129 #define DISABLE(irq) if (irq != -1) disable_irq(irq)
131 /* In micro second */
132 #define PLIP_DELAY_UNIT 1
134 /* Connection time out = PLIP_TRIGGER_WAIT * PLIP_DELAY_UNIT usec */
135 #define PLIP_TRIGGER_WAIT 500
137 /* Nibble time out = PLIP_NIBBLE_WAIT * PLIP_DELAY_UNIT usec */
138 #define PLIP_NIBBLE_WAIT 3000
141 static void plip_kick_bh(struct work_struct *work);
142 static void plip_bh(struct work_struct *work);
143 static void plip_timer_bh(struct work_struct *work);
145 /* Interrupt handler */
146 static void plip_interrupt(void *dev_id);
148 /* Functions for DEV methods */
149 static int plip_tx_packet(struct sk_buff *skb, struct net_device *dev);
150 static int plip_hard_header(struct sk_buff *skb, struct net_device *dev,
151 unsigned short type, const void *daddr,
152 const void *saddr, unsigned len);
153 static int plip_hard_header_cache(const struct neighbour *neigh,
154 struct hh_cache *hh);
155 static int plip_open(struct net_device *dev);
156 static int plip_close(struct net_device *dev);
157 static int plip_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
158 static int plip_preempt(void *handle);
159 static void plip_wakeup(void *handle);
161 enum plip_connection_state {
169 enum plip_packet_state {
178 enum plip_nibble_state {
185 enum plip_packet_state state;
186 enum plip_nibble_state nibble;
189 #if defined(__LITTLE_ENDIAN)
192 #elif defined(__BIG_ENDIAN)
196 #error "Please fix the endianness defines in <asm/byteorder.h>"
202 unsigned char checksum;
208 struct net_device *dev;
209 struct work_struct immediate;
210 struct delayed_work deferred;
211 struct delayed_work timer;
212 struct plip_local snd_data;
213 struct plip_local rcv_data;
214 struct pardevice *pardev;
215 unsigned long trigger;
216 unsigned long nibble;
217 enum plip_connection_state connection;
218 unsigned short timeout_count;
221 int should_relinquish;
224 struct completion killed_timer_cmp;
227 static inline void enable_parport_interrupts (struct net_device *dev)
231 struct parport *port =
232 ((struct net_local *)netdev_priv(dev))->pardev->port;
233 port->ops->enable_irq (port);
237 static inline void disable_parport_interrupts (struct net_device *dev)
241 struct parport *port =
242 ((struct net_local *)netdev_priv(dev))->pardev->port;
243 port->ops->disable_irq (port);
247 static inline void write_data (struct net_device *dev, unsigned char data)
249 struct parport *port =
250 ((struct net_local *)netdev_priv(dev))->pardev->port;
252 port->ops->write_data (port, data);
255 static inline unsigned char read_status (struct net_device *dev)
257 struct parport *port =
258 ((struct net_local *)netdev_priv(dev))->pardev->port;
260 return port->ops->read_status (port);
263 static const struct header_ops plip_header_ops = {
264 .create = plip_hard_header,
265 .cache = plip_hard_header_cache,
268 static const struct net_device_ops plip_netdev_ops = {
269 .ndo_open = plip_open,
270 .ndo_stop = plip_close,
271 .ndo_start_xmit = plip_tx_packet,
272 .ndo_do_ioctl = plip_ioctl,
275 /* Entry point of PLIP driver.
276 Probe the hardware, and register/initialize the driver.
278 PLIP is rather weird, because of the way it interacts with the parport
279 system. It is _not_ initialised from Space.c. Instead, plip_init()
280 is called, and that function makes up a "struct net_device" for each port, and
285 plip_init_netdev(struct net_device *dev)
287 struct net_local *nl = netdev_priv(dev);
289 /* Then, override parts of it */
290 dev->tx_queue_len = 10;
291 dev->flags = IFF_POINTOPOINT|IFF_NOARP;
292 memset(dev->dev_addr, 0xfc, ETH_ALEN);
294 dev->netdev_ops = &plip_netdev_ops;
295 dev->header_ops = &plip_header_ops;
300 /* Initialize constants */
301 nl->trigger = PLIP_TRIGGER_WAIT;
302 nl->nibble = PLIP_NIBBLE_WAIT;
304 /* Initialize task queue structures */
305 INIT_WORK(&nl->immediate, plip_bh);
306 INIT_DELAYED_WORK(&nl->deferred, plip_kick_bh);
309 INIT_DELAYED_WORK(&nl->timer, plip_timer_bh);
311 spin_lock_init(&nl->lock);
314 /* Bottom half handler for the delayed request.
315 This routine is kicked by do_timer().
316 Request `plip_bh' to be invoked. */
318 plip_kick_bh(struct work_struct *work)
320 struct net_local *nl =
321 container_of(work, struct net_local, deferred.work);
324 schedule_work(&nl->immediate);
327 /* Forward declarations of internal routines */
328 static int plip_none(struct net_device *, struct net_local *,
329 struct plip_local *, struct plip_local *);
330 static int plip_receive_packet(struct net_device *, struct net_local *,
331 struct plip_local *, struct plip_local *);
332 static int plip_send_packet(struct net_device *, struct net_local *,
333 struct plip_local *, struct plip_local *);
334 static int plip_connection_close(struct net_device *, struct net_local *,
335 struct plip_local *, struct plip_local *);
336 static int plip_error(struct net_device *, struct net_local *,
337 struct plip_local *, struct plip_local *);
338 static int plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
339 struct plip_local *snd,
340 struct plip_local *rcv,
348 typedef int (*plip_func)(struct net_device *dev, struct net_local *nl,
349 struct plip_local *snd, struct plip_local *rcv);
351 static const plip_func connection_state_table[] =
356 plip_connection_close,
360 /* Bottom half handler of PLIP. */
362 plip_bh(struct work_struct *work)
364 struct net_local *nl = container_of(work, struct net_local, immediate);
365 struct plip_local *snd = &nl->snd_data;
366 struct plip_local *rcv = &nl->rcv_data;
371 f = connection_state_table[nl->connection];
372 if ((r = (*f)(nl->dev, nl, snd, rcv)) != OK
373 && (r = plip_bh_timeout_error(nl->dev, nl, snd, rcv, r)) != OK) {
375 schedule_delayed_work(&nl->deferred, 1);
380 plip_timer_bh(struct work_struct *work)
382 struct net_local *nl =
383 container_of(work, struct net_local, timer.work);
385 if (!(atomic_read (&nl->kill_timer))) {
386 plip_interrupt (nl->dev);
388 schedule_delayed_work(&nl->timer, 1);
391 complete(&nl->killed_timer_cmp);
396 plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
397 struct plip_local *snd, struct plip_local *rcv,
402 * This is tricky. If we got here from the beginning of send (either
403 * with ERROR or HS_TIMEOUT) we have IRQ enabled. Otherwise it's
404 * already disabled. With the old variant of {enable,disable}_irq()
405 * extra disable_irq() was a no-op. Now it became mortal - it's
406 * unbalanced and thus we'll never re-enable IRQ (until rmmod plip,
407 * that is). So we have to treat HS_TIMEOUT and ERROR from send
411 spin_lock_irq(&nl->lock);
412 if (nl->connection == PLIP_CN_SEND) {
414 if (error != ERROR) { /* Timeout */
416 if ((error == HS_TIMEOUT
417 && nl->timeout_count <= 10)
418 || nl->timeout_count <= 3) {
419 spin_unlock_irq(&nl->lock);
420 /* Try again later */
423 c0 = read_status(dev);
424 printk(KERN_WARNING "%s: transmit timeout(%d,%02x)\n",
425 dev->name, snd->state, c0);
428 dev->stats.tx_errors++;
429 dev->stats.tx_aborted_errors++;
430 } else if (nl->connection == PLIP_CN_RECEIVE) {
431 if (rcv->state == PLIP_PK_TRIGGER) {
432 /* Transmission was interrupted. */
433 spin_unlock_irq(&nl->lock);
436 if (error != ERROR) { /* Timeout */
437 if (++nl->timeout_count <= 3) {
438 spin_unlock_irq(&nl->lock);
439 /* Try again later */
442 c0 = read_status(dev);
443 printk(KERN_WARNING "%s: receive timeout(%d,%02x)\n",
444 dev->name, rcv->state, c0);
446 dev->stats.rx_dropped++;
448 rcv->state = PLIP_PK_DONE;
453 snd->state = PLIP_PK_DONE;
455 dev_kfree_skb(snd->skb);
458 spin_unlock_irq(&nl->lock);
459 if (error == HS_TIMEOUT) {
461 synchronize_irq(dev->irq);
463 disable_parport_interrupts (dev);
464 netif_stop_queue (dev);
465 nl->connection = PLIP_CN_ERROR;
466 write_data (dev, 0x00);
472 plip_none(struct net_device *dev, struct net_local *nl,
473 struct plip_local *snd, struct plip_local *rcv)
478 /* PLIP_RECEIVE --- receive a byte(two nibbles)
479 Returns OK on success, TIMEOUT on timeout */
481 plip_receive(unsigned short nibble_timeout, struct net_device *dev,
482 enum plip_nibble_state *ns_p, unsigned char *data_p)
484 unsigned char c0, c1;
491 c0 = read_status(dev);
492 udelay(PLIP_DELAY_UNIT);
493 if ((c0 & 0x80) == 0) {
494 c1 = read_status(dev);
501 *data_p = (c0 >> 3) & 0x0f;
502 write_data (dev, 0x10); /* send ACK */
508 c0 = read_status(dev);
509 udelay(PLIP_DELAY_UNIT);
511 c1 = read_status(dev);
518 *data_p |= (c0 << 1) & 0xf0;
519 write_data (dev, 0x00); /* send ACK */
520 *ns_p = PLIP_NB_BEGIN;
528 * Determine the packet's protocol ID. The rule here is that we
529 * assume 802.3 if the type field is short enough to be a length.
530 * This is normal practice and works for any 'now in use' protocol.
532 * PLIP is ethernet ish but the daddr might not be valid if unicast.
533 * PLIP fortunately has no bus architecture (its Point-to-point).
535 * We can't fix the daddr thing as that quirk (more bug) is embedded
536 * in far too many old systems not all even running Linux.
539 static __be16 plip_type_trans(struct sk_buff *skb, struct net_device *dev)
544 skb_reset_mac_header(skb);
545 skb_pull(skb,dev->hard_header_len);
550 if(memcmp(eth->h_dest,dev->broadcast, ETH_ALEN)==0)
551 skb->pkt_type=PACKET_BROADCAST;
553 skb->pkt_type=PACKET_MULTICAST;
557 * This ALLMULTI check should be redundant by 1.4
558 * so don't forget to remove it.
561 if (ntohs(eth->h_proto) >= 1536)
567 * This is a magic hack to spot IPX packets. Older Novell breaks
568 * the protocol design and runs IPX over 802.3 without an 802.2 LLC
569 * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
570 * won't work for fault tolerant netware but does for the rest.
572 if (*(unsigned short *)rawp == 0xFFFF)
573 return htons(ETH_P_802_3);
578 return htons(ETH_P_802_2);
581 /* PLIP_RECEIVE_PACKET --- receive a packet */
583 plip_receive_packet(struct net_device *dev, struct net_local *nl,
584 struct plip_local *snd, struct plip_local *rcv)
586 unsigned short nibble_timeout = nl->nibble;
589 switch (rcv->state) {
590 case PLIP_PK_TRIGGER:
592 /* Don't need to synchronize irq, as we can safely ignore it */
593 disable_parport_interrupts (dev);
594 write_data (dev, 0x01); /* send ACK */
596 printk(KERN_DEBUG "%s: receive start\n", dev->name);
597 rcv->state = PLIP_PK_LENGTH_LSB;
598 rcv->nibble = PLIP_NB_BEGIN;
600 case PLIP_PK_LENGTH_LSB:
601 if (snd->state != PLIP_PK_DONE) {
602 if (plip_receive(nl->trigger, dev,
603 &rcv->nibble, &rcv->length.b.lsb)) {
604 /* collision, here dev->tbusy == 1 */
605 rcv->state = PLIP_PK_DONE;
607 nl->connection = PLIP_CN_SEND;
608 schedule_delayed_work(&nl->deferred, 1);
609 enable_parport_interrupts (dev);
614 if (plip_receive(nibble_timeout, dev,
615 &rcv->nibble, &rcv->length.b.lsb))
618 rcv->state = PLIP_PK_LENGTH_MSB;
620 case PLIP_PK_LENGTH_MSB:
621 if (plip_receive(nibble_timeout, dev,
622 &rcv->nibble, &rcv->length.b.msb))
624 if (rcv->length.h > dev->mtu + dev->hard_header_len
625 || rcv->length.h < 8) {
626 printk(KERN_WARNING "%s: bogus packet size %d.\n", dev->name, rcv->length.h);
629 /* Malloc up new buffer. */
630 rcv->skb = dev_alloc_skb(rcv->length.h + 2);
631 if (rcv->skb == NULL) {
632 printk(KERN_ERR "%s: Memory squeeze.\n", dev->name);
635 skb_reserve(rcv->skb, 2); /* Align IP on 16 byte boundaries */
636 skb_put(rcv->skb,rcv->length.h);
638 rcv->state = PLIP_PK_DATA;
643 lbuf = rcv->skb->data;
645 if (plip_receive(nibble_timeout, dev,
646 &rcv->nibble, &lbuf[rcv->byte]))
648 } while (++rcv->byte < rcv->length.h);
650 rcv->checksum += lbuf[--rcv->byte];
652 rcv->state = PLIP_PK_CHECKSUM;
654 case PLIP_PK_CHECKSUM:
655 if (plip_receive(nibble_timeout, dev,
656 &rcv->nibble, &rcv->data))
658 if (rcv->data != rcv->checksum) {
659 dev->stats.rx_crc_errors++;
661 printk(KERN_DEBUG "%s: checksum error\n", dev->name);
664 rcv->state = PLIP_PK_DONE;
667 /* Inform the upper layer for the arrival of a packet. */
668 rcv->skb->protocol=plip_type_trans(rcv->skb, dev);
669 netif_rx_ni(rcv->skb);
670 dev->stats.rx_bytes += rcv->length.h;
671 dev->stats.rx_packets++;
674 printk(KERN_DEBUG "%s: receive end\n", dev->name);
676 /* Close the connection. */
677 write_data (dev, 0x00);
678 spin_lock_irq(&nl->lock);
679 if (snd->state != PLIP_PK_DONE) {
680 nl->connection = PLIP_CN_SEND;
681 spin_unlock_irq(&nl->lock);
682 schedule_work(&nl->immediate);
683 enable_parport_interrupts (dev);
687 nl->connection = PLIP_CN_NONE;
688 spin_unlock_irq(&nl->lock);
689 enable_parport_interrupts (dev);
697 /* PLIP_SEND --- send a byte (two nibbles)
698 Returns OK on success, TIMEOUT when timeout */
700 plip_send(unsigned short nibble_timeout, struct net_device *dev,
701 enum plip_nibble_state *ns_p, unsigned char data)
708 write_data (dev, data & 0x0f);
712 write_data (dev, 0x10 | (data & 0x0f));
715 c0 = read_status(dev);
716 if ((c0 & 0x80) == 0)
720 udelay(PLIP_DELAY_UNIT);
722 write_data (dev, 0x10 | (data >> 4));
726 write_data (dev, (data >> 4));
729 c0 = read_status(dev);
734 udelay(PLIP_DELAY_UNIT);
736 *ns_p = PLIP_NB_BEGIN;
742 /* PLIP_SEND_PACKET --- send a packet */
744 plip_send_packet(struct net_device *dev, struct net_local *nl,
745 struct plip_local *snd, struct plip_local *rcv)
747 unsigned short nibble_timeout = nl->nibble;
752 if (snd->skb == NULL || (lbuf = snd->skb->data) == NULL) {
753 printk(KERN_DEBUG "%s: send skb lost\n", dev->name);
754 snd->state = PLIP_PK_DONE;
759 switch (snd->state) {
760 case PLIP_PK_TRIGGER:
761 if ((read_status(dev) & 0xf8) != 0x80)
764 /* Trigger remote rx interrupt. */
765 write_data (dev, 0x08);
768 udelay(PLIP_DELAY_UNIT);
769 spin_lock_irq(&nl->lock);
770 if (nl->connection == PLIP_CN_RECEIVE) {
771 spin_unlock_irq(&nl->lock);
773 dev->stats.collisions++;
776 c0 = read_status(dev);
778 spin_unlock_irq(&nl->lock);
780 synchronize_irq(dev->irq);
781 if (nl->connection == PLIP_CN_RECEIVE) {
783 We don't need to enable irq,
784 as it is soon disabled. */
785 /* Yes, we do. New variant of
786 {enable,disable}_irq *counts*
789 dev->stats.collisions++;
792 disable_parport_interrupts (dev);
794 printk(KERN_DEBUG "%s: send start\n", dev->name);
795 snd->state = PLIP_PK_LENGTH_LSB;
796 snd->nibble = PLIP_NB_BEGIN;
797 nl->timeout_count = 0;
800 spin_unlock_irq(&nl->lock);
802 write_data (dev, 0x00);
807 case PLIP_PK_LENGTH_LSB:
808 if (plip_send(nibble_timeout, dev,
809 &snd->nibble, snd->length.b.lsb))
811 snd->state = PLIP_PK_LENGTH_MSB;
813 case PLIP_PK_LENGTH_MSB:
814 if (plip_send(nibble_timeout, dev,
815 &snd->nibble, snd->length.b.msb))
817 snd->state = PLIP_PK_DATA;
823 if (plip_send(nibble_timeout, dev,
824 &snd->nibble, lbuf[snd->byte]))
826 } while (++snd->byte < snd->length.h);
828 snd->checksum += lbuf[--snd->byte];
830 snd->state = PLIP_PK_CHECKSUM;
832 case PLIP_PK_CHECKSUM:
833 if (plip_send(nibble_timeout, dev,
834 &snd->nibble, snd->checksum))
837 dev->stats.tx_bytes += snd->skb->len;
838 dev_kfree_skb(snd->skb);
839 dev->stats.tx_packets++;
840 snd->state = PLIP_PK_DONE;
843 /* Close the connection */
844 write_data (dev, 0x00);
847 printk(KERN_DEBUG "%s: send end\n", dev->name);
848 nl->connection = PLIP_CN_CLOSING;
850 schedule_delayed_work(&nl->deferred, 1);
851 enable_parport_interrupts (dev);
859 plip_connection_close(struct net_device *dev, struct net_local *nl,
860 struct plip_local *snd, struct plip_local *rcv)
862 spin_lock_irq(&nl->lock);
863 if (nl->connection == PLIP_CN_CLOSING) {
864 nl->connection = PLIP_CN_NONE;
865 netif_wake_queue (dev);
867 spin_unlock_irq(&nl->lock);
868 if (nl->should_relinquish) {
869 nl->should_relinquish = nl->port_owner = 0;
870 parport_release(nl->pardev);
875 /* PLIP_ERROR --- wait till other end settled */
877 plip_error(struct net_device *dev, struct net_local *nl,
878 struct plip_local *snd, struct plip_local *rcv)
880 unsigned char status;
882 status = read_status(dev);
883 if ((status & 0xf8) == 0x80) {
885 printk(KERN_DEBUG "%s: reset interface.\n", dev->name);
886 nl->connection = PLIP_CN_NONE;
887 nl->should_relinquish = 0;
888 netif_start_queue (dev);
889 enable_parport_interrupts (dev);
891 netif_wake_queue (dev);
894 schedule_delayed_work(&nl->deferred, 1);
900 /* Handle the parallel port interrupts. */
902 plip_interrupt(void *dev_id)
904 struct net_device *dev = dev_id;
905 struct net_local *nl;
906 struct plip_local *rcv;
910 nl = netdev_priv(dev);
913 spin_lock_irqsave (&nl->lock, flags);
915 c0 = read_status(dev);
916 if ((c0 & 0xf8) != 0xc0) {
917 if ((dev->irq != -1) && (net_debug > 1))
918 printk(KERN_DEBUG "%s: spurious interrupt\n", dev->name);
919 spin_unlock_irqrestore (&nl->lock, flags);
924 printk(KERN_DEBUG "%s: interrupt.\n", dev->name);
926 switch (nl->connection) {
927 case PLIP_CN_CLOSING:
928 netif_wake_queue (dev);
931 rcv->state = PLIP_PK_TRIGGER;
932 nl->connection = PLIP_CN_RECEIVE;
933 nl->timeout_count = 0;
934 schedule_work(&nl->immediate);
937 case PLIP_CN_RECEIVE:
938 /* May occur because there is race condition
939 around test and set of dev->interrupt.
940 Ignore this interrupt. */
944 printk(KERN_ERR "%s: receive interrupt in error state\n", dev->name);
948 spin_unlock_irqrestore(&nl->lock, flags);
952 plip_tx_packet(struct sk_buff *skb, struct net_device *dev)
954 struct net_local *nl = netdev_priv(dev);
955 struct plip_local *snd = &nl->snd_data;
957 if (netif_queue_stopped(dev))
958 return NETDEV_TX_BUSY;
960 /* We may need to grab the bus */
961 if (!nl->port_owner) {
962 if (parport_claim(nl->pardev))
963 return NETDEV_TX_BUSY;
967 netif_stop_queue (dev);
969 if (skb->len > dev->mtu + dev->hard_header_len) {
970 printk(KERN_WARNING "%s: packet too big, %d.\n", dev->name, (int)skb->len);
971 netif_start_queue (dev);
972 return NETDEV_TX_BUSY;
976 printk(KERN_DEBUG "%s: send request\n", dev->name);
978 spin_lock_irq(&nl->lock);
979 dev->trans_start = jiffies;
981 snd->length.h = skb->len;
982 snd->state = PLIP_PK_TRIGGER;
983 if (nl->connection == PLIP_CN_NONE) {
984 nl->connection = PLIP_CN_SEND;
985 nl->timeout_count = 0;
987 schedule_work(&nl->immediate);
988 spin_unlock_irq(&nl->lock);
994 plip_rewrite_address(const struct net_device *dev, struct ethhdr *eth)
996 const struct in_device *in_dev = dev->ip_ptr;
999 /* Any address will do - we take the first */
1000 const struct in_ifaddr *ifa = in_dev->ifa_list;
1002 memcpy(eth->h_source, dev->dev_addr, 6);
1003 memset(eth->h_dest, 0xfc, 2);
1004 memcpy(eth->h_dest+2, &ifa->ifa_address, 4);
1010 plip_hard_header(struct sk_buff *skb, struct net_device *dev,
1011 unsigned short type, const void *daddr,
1012 const void *saddr, unsigned len)
1016 ret = eth_header(skb, dev, type, daddr, saddr, len);
1018 plip_rewrite_address (dev, (struct ethhdr *)skb->data);
1023 static int plip_hard_header_cache(const struct neighbour *neigh,
1024 struct hh_cache *hh)
1028 ret = eth_header_cache(neigh, hh);
1032 eth = (struct ethhdr*)(((u8*)hh->hh_data) +
1033 HH_DATA_OFF(sizeof(*eth)));
1034 plip_rewrite_address (neigh->dev, eth);
1040 /* Open/initialize the board. This is called (in the current kernel)
1041 sometime after booting when the 'ifconfig' program is run.
1043 This routine gets exclusive access to the parallel port by allocating
1047 plip_open(struct net_device *dev)
1049 struct net_local *nl = netdev_priv(dev);
1050 struct in_device *in_dev;
1053 if (!nl->port_owner) {
1054 if (parport_claim(nl->pardev)) return -EAGAIN;
1058 nl->should_relinquish = 0;
1060 /* Clear the data port. */
1061 write_data (dev, 0x00);
1063 /* Enable rx interrupt. */
1064 enable_parport_interrupts (dev);
1067 atomic_set (&nl->kill_timer, 0);
1068 schedule_delayed_work(&nl->timer, 1);
1071 /* Initialize the state machine. */
1072 nl->rcv_data.state = nl->snd_data.state = PLIP_PK_DONE;
1073 nl->rcv_data.skb = nl->snd_data.skb = NULL;
1074 nl->connection = PLIP_CN_NONE;
1075 nl->is_deferred = 0;
1077 /* Fill in the MAC-level header.
1078 We used to abuse dev->broadcast to store the point-to-point
1079 MAC address, but we no longer do it. Instead, we fetch the
1080 interface address whenever it is needed, which is cheap enough
1081 because we use the hh_cache. Actually, abusing dev->broadcast
1082 didn't work, because when using plip_open the point-to-point
1083 address isn't yet known.
1084 PLIP doesn't have a real MAC address, but we need it to be
1085 DOS compatible, and to properly support taps (otherwise,
1086 when the device address isn't identical to the address of a
1087 received frame, the kernel incorrectly drops it). */
1089 if ((in_dev=dev->ip_ptr) != NULL) {
1090 /* Any address will do - we take the first. We already
1091 have the first two bytes filled with 0xfc, from
1093 struct in_ifaddr *ifa=in_dev->ifa_list;
1095 memcpy(dev->dev_addr+2, &ifa->ifa_local, 4);
1099 netif_start_queue (dev);
1104 /* The inverse routine to plip_open (). */
1106 plip_close(struct net_device *dev)
1108 struct net_local *nl = netdev_priv(dev);
1109 struct plip_local *snd = &nl->snd_data;
1110 struct plip_local *rcv = &nl->rcv_data;
1112 netif_stop_queue (dev);
1114 synchronize_irq(dev->irq);
1118 init_completion(&nl->killed_timer_cmp);
1119 atomic_set (&nl->kill_timer, 1);
1120 wait_for_completion(&nl->killed_timer_cmp);
1124 outb(0x00, PAR_DATA(dev));
1126 nl->is_deferred = 0;
1127 nl->connection = PLIP_CN_NONE;
1128 if (nl->port_owner) {
1129 parport_release(nl->pardev);
1133 snd->state = PLIP_PK_DONE;
1135 dev_kfree_skb(snd->skb);
1138 rcv->state = PLIP_PK_DONE;
1140 kfree_skb(rcv->skb);
1146 outb(0x00, PAR_CONTROL(dev));
1152 plip_preempt(void *handle)
1154 struct net_device *dev = (struct net_device *)handle;
1155 struct net_local *nl = netdev_priv(dev);
1157 /* Stand our ground if a datagram is on the wire */
1158 if (nl->connection != PLIP_CN_NONE) {
1159 nl->should_relinquish = 1;
1163 nl->port_owner = 0; /* Remember that we released the bus */
1168 plip_wakeup(void *handle)
1170 struct net_device *dev = (struct net_device *)handle;
1171 struct net_local *nl = netdev_priv(dev);
1173 if (nl->port_owner) {
1174 /* Why are we being woken up? */
1175 printk(KERN_DEBUG "%s: why am I being woken up?\n", dev->name);
1176 if (!parport_claim(nl->pardev))
1177 /* bus_owner is already set (but why?) */
1178 printk(KERN_DEBUG "%s: I'm broken.\n", dev->name);
1183 if (!(dev->flags & IFF_UP))
1184 /* Don't need the port when the interface is down */
1187 if (!parport_claim(nl->pardev)) {
1189 /* Clear the data port. */
1190 write_data (dev, 0x00);
1197 plip_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1199 struct net_local *nl = netdev_priv(dev);
1200 struct plipconf *pc = (struct plipconf *) &rq->ifr_ifru;
1202 if (cmd != SIOCDEVPLIP)
1206 case PLIP_GET_TIMEOUT:
1207 pc->trigger = nl->trigger;
1208 pc->nibble = nl->nibble;
1210 case PLIP_SET_TIMEOUT:
1211 if(!capable(CAP_NET_ADMIN))
1213 nl->trigger = pc->trigger;
1214 nl->nibble = pc->nibble;
1222 static int parport[PLIP_MAX] = { [0 ... PLIP_MAX-1] = -1 };
1225 module_param_array(parport, int, NULL, 0);
1226 module_param(timid, int, 0);
1227 MODULE_PARM_DESC(parport, "List of parport device numbers to use by plip");
1229 static struct net_device *dev_plip[PLIP_MAX] = { NULL, };
1232 plip_searchfor(int list[], int a)
1235 for (i = 0; i < PLIP_MAX && list[i] != -1; i++) {
1236 if (list[i] == a) return 1;
1241 /* plip_attach() is called (by the parport code) when a port is
1242 * available to use. */
1243 static void plip_attach (struct parport *port)
1246 struct net_device *dev;
1247 struct net_local *nl;
1248 char name[IFNAMSIZ];
1250 if ((parport[0] == -1 && (!timid || !port->devices)) ||
1251 plip_searchfor(parport, port->number)) {
1252 if (unit == PLIP_MAX) {
1253 printk(KERN_ERR "plip: too many devices\n");
1257 sprintf(name, "plip%d", unit);
1258 dev = alloc_etherdev(sizeof(struct net_local));
1260 printk(KERN_ERR "plip: memory squeeze\n");
1264 strcpy(dev->name, name);
1266 dev->irq = port->irq;
1267 dev->base_addr = port->base;
1268 if (port->irq == -1) {
1269 printk(KERN_INFO "plip: %s has no IRQ. Using IRQ-less mode,"
1270 "which is fairly inefficient!\n", port->name);
1273 nl = netdev_priv(dev);
1275 nl->pardev = parport_register_device(port, dev->name, plip_preempt,
1276 plip_wakeup, plip_interrupt,
1280 printk(KERN_ERR "%s: parport_register failed\n", name);
1285 plip_init_netdev(dev);
1287 if (register_netdev(dev)) {
1288 printk(KERN_ERR "%s: network register failed\n", name);
1289 goto err_parport_unregister;
1292 printk(KERN_INFO "%s", version);
1294 printk(KERN_INFO "%s: Parallel port at %#3lx, "
1296 dev->name, dev->base_addr, dev->irq);
1298 printk(KERN_INFO "%s: Parallel port at %#3lx, "
1300 dev->name, dev->base_addr);
1301 dev_plip[unit++] = dev;
1305 err_parport_unregister:
1306 parport_unregister_device(nl->pardev);
1312 /* plip_detach() is called (by the parport code) when a port is
1313 * no longer available to use. */
1314 static void plip_detach (struct parport *port)
1319 static struct parport_driver plip_driver = {
1321 .attach = plip_attach,
1322 .detach = plip_detach
1325 static void __exit plip_cleanup_module (void)
1327 struct net_device *dev;
1330 parport_unregister_driver (&plip_driver);
1332 for (i=0; i < PLIP_MAX; i++) {
1333 if ((dev = dev_plip[i])) {
1334 struct net_local *nl = netdev_priv(dev);
1335 unregister_netdev(dev);
1337 parport_release(nl->pardev);
1338 parport_unregister_device(nl->pardev);
1347 static int parport_ptr;
1349 static int __init plip_setup(char *str)
1353 str = get_options(str, ARRAY_SIZE(ints), ints);
1356 if (!strncmp(str, "parport", 7)) {
1357 int n = simple_strtoul(str+7, NULL, 10);
1358 if (parport_ptr < PLIP_MAX)
1359 parport[parport_ptr++] = n;
1361 printk(KERN_INFO "plip: too many ports, %s ignored.\n",
1363 } else if (!strcmp(str, "timid")) {
1366 if (ints[0] == 0 || ints[1] == 0) {
1367 /* disable driver on "plip=" or "plip=0" */
1370 printk(KERN_WARNING "warning: 'plip=0x%x' ignored\n",
1377 __setup("plip=", plip_setup);
1379 #endif /* !MODULE */
1381 static int __init plip_init (void)
1383 if (parport[0] == -2)
1386 if (parport[0] != -1 && timid) {
1387 printk(KERN_WARNING "plip: warning, ignoring `timid' since specific ports given.\n");
1391 if (parport_register_driver (&plip_driver)) {
1392 printk (KERN_WARNING "plip: couldn't register driver\n");
1399 module_init(plip_init);
1400 module_exit(plip_cleanup_module);
1401 MODULE_LICENSE("GPL");